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Computer support for the development of listening skills by children with profound and multiple disabilities
Focus: Early Intervention
Topic: MDVI
Paul Blenkhorn : Gareth Evans
Professor : Senior Lecturer
Department of Computation
UMIST
PO Box 88
Manchester
M60 1QD
United Kingdom
+44-161-200-3371
p.blenkhorn@co.umist.ac.uk
Since the mid 1980’s we have been working in the area of using of computers to provide sensory stimulation to children and adults with profound and multiple disabilities [1, 2]. Much of this work has been concerned with visual stimulation and can be seen to have been inspired by the (not computer-based) work of Barraga [3, 4], the Research Centre for the Education of the Visually Handicapped (RCEVH) “Look and Think” project [5], and also the work of Lili Nielsen [6]. Their work showed that by providing focussed stimulation (visual in the case of Barraga and RCEVH) users could “learn” to improve their use of their senses and (more in the case of Nielsen) develop their sensory and cognitive engagement with the world. As multimedia computers became more prevalent in UK schools (towards the mid 1990s) further developments have exploited using multimedia computer systems for sensory stimulation, both visual and auditory [7, 8, 9, 10]
This paper focuses on one aspect of this work, namely, using a multimedia computer system to present sound-based activities to promote the development of listening skills by children with profound and multiple disabilities.
In this section we present a simple framework for the development of listening skills. This framework is derived by analogy from a framework for the development of visual skills (which we present in [10]) which is in turn derived from the work presented in [5].
The framework is presented as if it were sequential, i.e. the development of a later skill is dependent upon the acquisition of the set of earlier skills. However, whilst it is true that the first skill (a basic awareness of sound) is a prerequisite of the later skills and that the second skill (the discrimination of sounds) is a prerequisite for the user to control certain software activities, it is not clear to us whether the later skills build on each other or may be acquired in parallel.
The skills are:
In this stage the client becomes aware that there is an auditory world that they may wish to pay attention to. In this case the software packages present sounds, these may be fixed in space or moving (sound movement is discussed later). In our experience laughter and bodily sounds (especially those that are considered to be slightly rude) have the greatest impact on children.
In this stage the client becomes aware of the differences between sounds and is able to associate meaning with each. A typical example that is used with children (which can also be used with visual stimulation if the user has some sight) is the sounds of common domestic and farm animals.
In this stage the client becomes aware of the direction from which a sound is produced. Using a conventional computer with two speakers we are largely restricted to three directions, left, right and ahead. Computer systems with more sophisticated sound cards and multiple speakers can allow, in theory, the sound to be positioned in any position in the horizontal plane relative to the client’s head. In practice, resolution in the left-right field ahead of the user is quite good (and certainly an improvement over two speaker systems) but resolution in other directions is poor.
In this stage the client becomes aware that sounds can move from one position to another. Again with conventional computer systems with two speakers, movement is limited to three directions (left, right and ahead). Three-dimensional sound systems can produce more sophisticated movements, including movement behind a user.
In this stage the client develops skills in separating sounds from one another. It is directly inspired by visual skills development, in which ‘objects’ are placed on increasingly complex visual backgrounds. In the case of sounds, a sound can be overlaid on a background sound to produce a more complex auditory environment. The relative volumes of the ‘foreground’ to the ‘background’ sounds can be controlled.
The software packages and a number of their associated applications have developed in collaboration the CAMI (Computers and Multi Impaired[1]) group. The CAMI group is UK based and is made up of teachers, advisors, carers, parents and technologists who have an interest in the use of computer-based activities with profoundly disabled children and adults.
The CAMI group has inspired the development of software and activities in two ways. Activities have been develop to meet the specific needs of individual clients and also from a more abstract pedagogical standpoint based on the general experience of members of the group.
In this section we describe three software packages that illustrate how computer-based support may be given to the development of listening skills. The three packages are Carousel, Look ’n Listen, and Listen Hear (V2). The last mentioned will be released shortly and is currently undergoing final testing. Before describing the software, we firstly make some general comments concerning the control of the software.
The teacher[2] can control software, the presentation of auditory information to the client. In this mode of operation the software becomes a tool through which the teacher can present various sounds and control how and where they are played.
Carousel [11] is a relatively simple program that was inspired by a slide projector. The user steps through a sequence of frames. Each time the user activates a switch the next frame is presented. The sequence of frames is fixed and when the user reaches the end of the sequence the first frame is loaded. Each frame can contain a picture (possibly animated), some text, and, of relevance here, a sound. Thus, from an auditory viewpoint, the package simply presents a sequence of sounds. Teachers can create activities by using sounds from many sources (the Internet is a great resource) and record their own.
Carousel is generally used a visual activity with the sounds supporting the pictures or providing some spoken narration. However, some teachers have created activities that have no visual context at all. For example, one CAMI group member working with deaf-blind clients has reported very positive results in using a Carousel activity with a young deaf-blind woman. The activity consists of simply playing a different laugh each time that the woman presses the switch. The carer reports that the woman, who is generally somewhat sullen and passive, smiles and engages with this piece of software.
Carousel can be used to support the development of awareness and, when supported by a teacher, the development of discrimination type activities.
Look ’n Listen is somewhat similar to Carousel in that it presents a sequence of frames consisting of pictures, text and sound. Its major differences are that a frame is divided into two halves (as shown for a visual activity in Figure 1) and that the client has two switches.
Figure 1: A Look ’n Listen activity, displaying two pictures
Sounds can also be positioned to the left, the right or directly ahead. The user can discriminate position on a computer with a conventional stereo sound card.
Two types of activity are supported for the development of sound discrimination skills.
Here different types of sounds (and pictures) are associated with the left switch and the right switch. So, for example, one activity has people-based sounds (and associated images) on the left switch and transportation-based sounds (and associated images) on the right switch. The user has independent control of the two halves (the left switch matches the left hand sound/image and the right switch matches the right hand sound image. In this way the user is encouraged to discriminate between different types of sound.
In this activity one or two pictures are displayed on the screen and a sound is played. One of the switches corresponds to the “correct” response and steps to the next frame; the other switch causes the current “frame” to be redisplayed. The screen in Figure 1 is the example of such an activity. A sheep sound is played from the left speaker and the user is expected to press the switch on the left. The activity is not entirely dependent on vision, and indeed when encouraging the development of sound localisation it may work best with the screen switched off. The fact that the sound is coming from the left speaker should be sufficient.
Look ’n Listen can be used to support the development of sound discrimination and sound localisation skills.
This package is primarily designed to allow a teacher or a client to control the location and movement of sound in space to support the development of localisation and tracking skills. An earlier version of the software enabled the teacher to control a sound to appear from the left, from the right or firstly ahead of the client.
Recently this package has been update (to Listen Hear V2) to support all five of the activity areas specified in the previous section. It provides explicit support for the development of tracking skills by allowing sounds to be moved around the user’s head using multiple speaker 3D sound cards. The sounds can be moved by the teacher or the client (using a mouse or joystick) or in predefined patterns provided by the software. The software includes a number of predefined patterns including, for example left to right, front left to back, in a circle, etc. The sounds can be set to move in 3D space.
Listen Hear V2 also provides support for foreground/background contrasts by playing a sound over backing music. The relative volume of the sound and background track can be controlled and the background track can be selected from a set that have varying degrees of complexity.
Carousel is freely available. Look ’n Listen and Listen Hear are commercially available in a number of countries including the UK, USA, Australia, and Argentina as well as several western European countries.
The major defect of the work described in this paper is the lack of systematic evaluation. We hope to attract collaborators who wish to carry out this work.
The authors wish acknowledge the support of the CAMI (Computers and Multi Impaired) group for feedback and support during the development of this work. Particular thanks are due to Chris Painter and the RNIB’s Condover Hall School.
11. Blenkhorn, P., Painter, C. & Evans, D. G. (2000) Applications of Carousel: A Simple Program for use by Adults and Children with Profound and Multiple Disabilities. 7th International Conference on Computers Helping People with Special Needs, Karlsruhe, Germany. Ed. R.Vollmar and R. Wagner, Österreicchische Computer Gesellschaft 2000, pp. 175-181.
[1] Further information about the CAMI group can be obtained by contacting the authors
[2] In this paper we use the term ‘teacher’ to refer to the person who is using the software with the client.
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